scholarly journals Extrinsic and Intrinsic Factors Regulating Juvenile Refractive Development and Eye Growth

2021 ◽  
Vol 62 (14) ◽  
pp. 21
Author(s):  
Kai Yip Choi ◽  
Henry Ho-lung Chan
Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 406
Author(s):  
Nicola Zerbinati ◽  
Sabrina Sommatis ◽  
Cristina Maccario ◽  
Serena Di Francesco ◽  
Maria Chiara Capillo ◽  
...  

Skin ageing has many manifestations such as wrinkles, dryness, hyperpigmentation, and uneven skin tone. Extrinsic and intrinsic factors, especially solar ultraviolet light (UVB), contribute to skin ageing; its main features are brown spots, alterations in melanin pigmentation, and a decrease in collagen and hyaluronic acid linked to oxidative stress. Several studies showed that topical products containing ingredients with antioxidant activity can reduce oxidative damage; to provide a maximum anti-ageing effect to the skin, topical products can combine various ingredients. C-SHOT SERUM contains a combination of two molecules with a proven anti-ageing activity: a high percentage (30%) of a more stable vitamin C derivative, 3-O-ethyl-l-ascorbic acid, and lactic acid (1%). The product showed a high biocompatibility, assessed through an MTT assay on keratinocytes and on Reconstructed Human Epidermis (RHE, SkinEthic); the anti-ageing activity was demonstrated on human dermal fibroblasts and keratinocytes by a statistically significant increase in collagen production and a reduction of a UVB-induced DNA damage marker (γ-H2AX histone), indicating DNA protection. Moreover, a depigmenting activity, shown by a highly significant decrease in melanin content on treated Reconstructed Human Pigmented Epidermis (RHPE), was assessed. According to the data of our study, the tested product contrasts the effect of skin ageing and irregular pigmentation due to the physiological decline of the skin.


2019 ◽  
Vol 26 (1) ◽  
pp. 155-178 ◽  
Author(s):  
Stephen Pratt ◽  
Christine YH Zeng

Counterfeiting of fashion brands is a multi-billion dollar industry with an increasing number of goods being counterfeited. This research takes a demand-side approach to measuring counterfeiting activity among tourists in Hong Kong. Non-deceptive counterfeit purchases by tourists in Hong Kong amount to US$761.32 million per year. Tourists’ decision of whether to purchase counterfeit goods depended on a mix of extrinsic and intrinsic factors including psychometric variables, trip-related characteristics, and sociodemographics. Lowering the prices of genuine goods and explaining the risks of purchasing counterfeit goods would be the most effective anti-counterfeit measures. However, lowering the price of genuine goods can diminish the brand image of these luxury items.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Pilar Mata Tutor ◽  
Catherine Villoria Rojas ◽  
María Benito Sánchez

Decomposition is a natural process that begins approximately four minutes after death and continues until the body is degraded to simpler biochemical components which are gradually recycled back to the environment. This process is dependent on extrinsic and intrinsic factors. Embalming is a chemical preservation technique that aims to preserve the external appearance of the body in good condition for an indeterminate period. In Spain, there is a lack of experimental studies carried out to analyse the variables that affect decomposition in embalmed bodies, therefore, in accordance with the conclusions reached by previous authors, it is hypothesised that embalmed bodies show quantifiable characteristics during the late stage decomposition which distinguish them from control, unembalmed, cadavers. An anthropological and statistical analysis was performed on 14 individuals from Cementerio Sur de Madrid exhumed after ten years according to the Mortuary Health Law of the Autonomous Region of Madrid. The preliminary results obtained showed that there is a qualitative and statistically significant relationship between the variables evaluated, being the presence or absence of soft tissue the most notable difference. The mortuary or thanatopraxy treatments performed before the burial and the microenvironmental conditions of the burial positively influence the soft tissue preservation on embalmed bodies. These results contribute to the understanding about the decomposition rate of an embalmed cadavers in cemeteries, and the related extrinsic variables.


Author(s):  
Heron Teixeira

Introduction: Estimating the time of death is an important task in day-to-day forensic work and many factors for its designation are understood, one of which is rigor mortis. They can be altered by extrinsic and intrinsic factors, such as temperature location, humidity, heat, age, sex, length and body weight, and can be used as a parameter for approximate identification of the time of death. Objective: To carry out a brief review on the topic in order to promote a better understanding of the subject addressed and fully understand its physiology. Materials and Methods: Pubmed, Scielo and Medline databases were searched without date restrictions for articles published in English and Portuguese using the descriptors rigor mortis, autolysis and changes after death. Results: The theme presents consolidated researches regarding its natural course, being an important tool to estimate the time of death along other signs that appear after death, as well as to estimate some causes of death. Conclusion: Understanding the development of rigor mortis, helps to identify and distinguish processes that may have led to death and the post-mortem time.


1934 ◽  
Vol 60 (1) ◽  
pp. 19-35 ◽  
Author(s):  
Kenneth Goodner

The power of specific antipneumococcus serum to protect rabbits against infection with Type I Pneumococcus has been studied with reference to the capacity of the animal to utilize the specific antibodies. Under conditions ensuring relatively controlled genetic factors it was found that heavier animals and those with high white blood cell counts are much better able to utilize the passively conferred immune principles. The interrelationships of the extrinsic and intrinsic factors responsible for immunity have been discussed.


2020 ◽  
Author(s):  
Emilie Vangrinsven ◽  
Fastrès Aline ◽  
Taminiau Bernard ◽  
Frédéric Billen ◽  
Daube Georges ◽  
...  

Abstract Background – Extrinsic and intrinsic factors have been shown to influence nasal microbiota (NM) in humans. Very few studies investigated the association between nasal microbiota and factors like facial/body conformation, age, and environment in dogs. Objectives are to investigate variations in NM in healthy dogs with different facial and body conformations and to assess the influence of age and living environment. A total of 46 dogs of different age, living environment and from 3 different breed groups were recruited: 22 meso-/dolichocephalic medium to large breed dogs, 12 brachycephalic dogs and 12 terrier breeds. The nasal bacterial microbiota was assessed through sequencing of 16S rRNA gene (V1-V3 regions) amplicons.Results – We showed major differences in the NM composition together with increased richness and α-diversity in brachycephalic dogs, compared to meso-/dolichocephalic dogs and dogs from terrier breeds. We failed to detect any effect of age or environment.Conclusion – Healthy brachycephalic breeds and their unique facial conformation is associated with a distinct NM profile. Description of the NM in healthy dogs serves as a foundation for future researches assessing the changes associated with disease and the modulation of NM communities as a potential treatment.


2019 ◽  
Author(s):  
Tatiana V. Tkatchenko ◽  
Rupal L. Shah ◽  
Takayuki Nagasaki ◽  
Andrei V. Tkatchenko ◽  
◽  
...  

AbstractPopulation studies suggest that genetic factors play an important role in refractive error development; however, the precise role of genetic background and the composition of the signaling pathways underlying refractive eye development remain poorly understood. Here, we analyzed normal refractive development and susceptibility to form-deprivation myopia in the eight progenitor mouse strains of the Collaborative Cross (CC). Genetic background strongly influenced both baseline refractive development and susceptibility to environmentally-induced myopia. Baseline refractive errors ranged from −21.2 diopters (D) in 129S1/svlmj mice to +22.0 D in CAST/EiJ mice and represented a continuous distribution typical of a quantitative genetic trait. The extent of induced form-deprivation myopia ranged from −5.6 D in NZO/HILtJ mice to −20.0 D in CAST/EiJ mice and also followed a continuous distribution. Whole-genome (RNA-seq) gene expression profiling in retinae from CC progenitor strains identified genes whose expression level correlated with either baseline refractive error or susceptibility to myopia. Expression levels of 2,302 genes correlated with the baseline refractive state of the eye, whereas 1,917 genes correlated with susceptibility to induced myopia. Genome-wide gene-based association analysis in the CREAM and UK Biobank human cohorts revealed that 985 of the above genes were associated with refractive error development in humans, including 847 genes which were implicated in the development of human myopia for the first time. Although the gene sets controlling baseline refractive development and those regulating susceptibility to myopia overlapped, these two processes appeared to be controlled by largely distinct sets of genes. Comparison with data for other animal models of myopia revealed that the genes identified in this study comprise a well-defined set of retinal signaling pathways, which are highly conserved across different species. These results provide attractive targets for the development of anti-myopia drugs.Author SummarySeveral lines of evidence suggest that variations in genetic background have a strong impact on a default (baseline) trajectory of eye growth and refractive development. Many studies also highlighted differences in susceptibility of different individuals to environmentally induced changes in refractive eye development, suggesting that genetic background plays an important role in visual regulation of eye growth. However, genes and signaling pathways that control the baseline trajectory of refractive eye development and those that regulate the impact of visual environment on refractive eye development are still poorly understood. Our data suggest that both processes are regulated by elaborate retinal genetic networks. Surprisingly, we found that although genes that control baseline refractive eye development and genes regulating the impact of visual environment on refractive development overlap, there is a large number of genes and pathways which exclusively control either the baseline trajectory of refractive eye development or the impact of visual environment on refractive development. Moreover, we found that many of the genes and pathways, which we found to be associated with either baseline refractive development or susceptibility to environmentally induced myopia in mice, are also associated with refractive error development in the human population and are highly conserved across different species. Identification of genes and pathways that underlie visual regulation of eye growth versus genes and pathways that control default trajectory of refractive eye development sheds light on the basic mechanisms of eye emmetropization and provides previously unexplored possibilities for the development of new treatment options for myopia.


2016 ◽  
Vol 6 (9) ◽  
pp. 20 ◽  
Author(s):  
Stephen Morangi Nyambegera ◽  
Caroline Njambi Gicheru

<p>The purpose of the study was to determine the factors that influence employee motivation in Kenyan Organizations. The study was guided by the following research questions: (i) what are the extrinsic factors that influence employee motivation in AMREF Health Africa in Kenya? (ii) what intrinsic factors influence employee motivation in AMREF Health Africa in Kenya? A descriptive research design was adopted. Stratified random sampling technique was used to draw a sample size of 96 respondents. The data collection instrument was a structured questionnaire developed by the researchers.  A set of descriptive and correlation statistics were adopted for analysis. The study identified several intrinsic factors that influence employee motivation. These included employee achievements, recognition, work itself, responsibility and advancement, salary structure, the level to which the employees feel appreciated, and the employee perception of their jobs among other factors. The study further, established that the intrinsic factors that influence employee motivation include empowerment and autonomy, employees’ view of their work, organization trust, skill variety requirements among others. The study recommends that the organization should acknowledge and make use of a proper mix of extrinsic and intrinsic factors in their human resource management practices to ensure that employees are well motivated to perform their tasks.</p>


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